Plug connectors and glass fiber connectors are known, inter alia, from EP 0 590 586 A1 or from U.S. Pat. No. 5,317,663. This coupling for glass fiber connectors can be inserted into a front panel from the front face, and also discloses a coupling which can be locked by means of latching springs which engage behind the front panel. The coupling for glass fiber connectors comprises a housing with two ends, which are in the form of front and rear plug holders, for holding plugs, as well as flanges which project from the housing, suitable for making contact with the front panel and for locking the couple there with at least one latching spring which is arranged on the coupling in order to engage behind the front panel. A latching spring such as this has two spring tabs on opposite sides of the rear plug holder. The latching springs are in the form of leaf springs which engage though a corresponding aperture in the front panel and thus lock the coupling in the front panel. For this purpose, the leaf spring or spring tongue can be pressed to such an extent against the coupling housing that the leaf spring or the spring tab passes through the front panel in the pushed-in state, and then spreads. The use of a coupling or coupling device such as this is dependant on the front panel having appropriate apertures, and the front panel must be provided by means of an appropriate configuration with a specific aperture in order to lock couplings there; the coupling must be released from the rear face of the front panel.
In addition, plug connectors having latching devices which can be released from the front face of a housing or of a front panel and which project from the front panel are known from telephone technology and from local area networks (EP 0 766 350 A2) In this case, inadvertent release is possible, and a relatively large amount of space is required to manually grip the latching device.